Factors influencing the luminescence intensity of europium(III) complexes prepared via synergistic extraction

► β-Diketone (HA) in solution influences the luminescence intensity of EuA3. ► The influence of HA to CHCl3 extracted Eu(III) is different from that for CHCl3 dissolved complex. ► The difference is ascribed to the water molecules coordinated to Eu(III). ► Excess HA does not influence the intensity of Eu(III) in the extraction with HA and Lewis bases. ► Use of synergistic extraction is efficient to prepare phosphor in solution.